Abstract Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive disorder caused by mutations in the gene encoding the 7-dehydrocholesterol reductase (7-DHC) resulting in decreased or absent function of this enzyme responsible…
Abstract Trisomy 18 (Edwards syndrome) is the second most common autosomal trisomy in newborns. More than 90% of cases are the result of maternal nondisjunction of chromosome 18. Fetuses with…
Abstract Trisomy 13 (Patau syndrome) is the third most common autosomal trisomy in newborns. It results from an extra chromosome 13 secondary to nondisjunction or translocation. In the United States,…
Abstract VACTERL ( v ertebral, a nal, c ardiac, t racheal, e sophageal, r enal, and l imb anomalies) association is a nonrandom association of congenital malformations. Associated findings of…
Abstract Aneuploidy is an abnormal copy number of one or more chromosomes and arises from aberrations in cell division. The most common anueploid conditions that can result in live birth…
Abstract Noonan syndrome is a disorder characterized by specific facial dysmorphisms, cardiovascular defects, short stature, and variable developmental delay. Noonan syndrome should be suspected prenatally in any fetus with cystic…
Abstract Poland sequence refers to a congenital unilateral absence of the sternal costal portion of the pectoralis major muscle and ipsilateral upper limb anomalies. The incidence of Poland sequence is…
Abstract Roberts syndrome is a rare genetic disorder characterized by fetal growth restriction, limb reductions, and craniofacial abnormalities. Upper extremities are more severely affected than lower extremities. It is caused…
Abstract Prune-belly syndrome is characterized by urologic abnormalities, flaccidity, or dysplasia in abdominal wall musculature, and cryptorchidism (in males). Because of the poorly developed abdominal wall muscles, the infant’s abdomen…
